The Gravity Assist Podcast is hosted by NASA’s Director of Planetary Science, Jim Green, who each week talks to some of the greatest planetary scientists on the planet, giving a guided tour through the Solar System and beyond in the process. This week, he’s joined by New Horizons Principal Investigator Alan Stern of the Southwest Research Institute, to chat about what the July 2015 fly-by of Pluto revealed about this mysterious and diverse world, which has a heart-shaped glacier that’s the size of Texas and Oklahoma, blue skies, spinning moons, mountainsas high as the Rockies, and red snow!